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Major, Trace And Rare Earth Element Concentrations In Nist Standard Reference Material® 1646a Analyzed By Als Global Using Method Me-Ms61r, Jane L. Alexander

Publications and Research

This technical note compares analytical results obtained from ALS Global Method ME-MS61r with the certified and previously published results for NIST Standard Reference Material® 1646a, Estuarine Sediment. The results are grouped into major, trace and rare earth elements, and focus on elements used by sedimentary geochemists, for example in studies of sediment provenance. The results from ALS Global Method ME-MS61r are internally consistent and generally robust when compared with published analyses. However, acid digestion may not completely dissolve resistant minerals, leading to under-reporting of some elements such as Ti, Cr, Zr, heavy REE and Y.

Lead Exposure In The 21st Century: Modeling A Path From Crisis To Prevention, Danlin Yu

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

No abstract provided.

Maize Yield Stability Under Organic And Conventional Farming Systems In Sub-Humid Agro-Ecozones Of Central Kenya, Milka Kiboi, David Bautze, Felix Matheri, Amritbir Riar, Andreas Fliessbach

All Peer-Reviewed Publications

Maize (Zea mays L.) is the main staple crop and is important to the food security and livelihoods of people globally. We evaluated the effects of organic and conventional farming systems on maize grain yield and temporal yield stability under different external input levels in a long-term experiment (2007–2022) at two sites in Kenya. We implemented four farming systems: organic high (Org-High), conventional high (Conv-High), organic low (Org-Low), and conventional low (Conv-Low) in a randomized complete block design. Growth indicators for maize, height, stem diameter, and grain yield were higher in high input systems, but grain yield stability was not. …

Miscanthus × Giganteus Increases Soil Maximum Water Holding Capacity Compared To Maize, Jessica T. Nelson, Maoz Dor, Andy D. Vanloocke, Jacob E. Studt, Perla K. Schrock, Marshall D. Mcdaniel

School of Earth, Environmental, & Marine Sciences Faculty Publications

Soil ecosystem services, like the ability to store water, have been depleted after a century of conventional, annual cropping, and perennial crops offer a solution to this and other agricultural environmental issues. We assessed the impact of Miscanthus × giganteus (miscanthus), a perennial biomass crop, on soil water holding capacity and structure compared to continuous maize (Zea mays L.) at two sites in Iowa. After three growing seasons, we measured the following: (1) maximum water holding capacity (MWHC) with and without soil structure, and (2) total porosity and pore size distribution (PSD) via micro-computed tomography (microCT). Miscanthus increased MWHC …

Comparative Analysis Of Different Magnetic Anomaly Datasets Using Navigation Performance With Flight Test Data, Aaron P. Nielsen, Brandon M. Blakely, Patrick Duff

Faculty Publications

Magnetic Anomaly Navigation (MagNav) is a map-based method of navigation which relies on accurately obtaining the anomaly field to a high level of precision to achieve good navigation results. This requires utilizing high quality sensors, accurately modeling disturbance fields from the aircraft & other sources, and creating high-fidelity maps. Aeromagnetic survey data or marine track survey data must be processed into a product that can be used as a reference for a magnetic navigator and a variety of techniques can be utilized for this processing. The data collection for different survey types reflects choices typically made to study the underlying …

Compound-Specific Isotope Records Of Dust Provenance And Hydroclimate In The North Pacific And Marginal Seas Of East Asia: Integrating N-Alkane Δ13c And Δd With Standardized Analytical Frameworks, Julian W. Traphagan

LSU Doctoral Dissertations

This dissertation presents advancements in compound-specific isotope analysis (CSIA) through methodological innovation and paleoclimate reconstruction in Central and East Asia. Utilizing plant wax n-alkanes from International Ocean Discovery Program (IODP) and Ocean Drilling Program (ODP) sediment cores, this research reconstructs atmospheric circulation shifts responding to tectonic evolution and climate transitions since the Late Miocene.

Chapter 1 investigates hydrogen isotope compositions (δD_wax) from IODP U1430 (Sea of Japan), ODP 886, and ODP 1208 (North Pacific) to trace dust provenance and hydroclimate changes since ~13 Ma. Results reveal persistently segmented source-to-sink systems: the Sea of Japan dominated by westerly …

Effect Of Seasonal Variability In Methane Emissions And Iron Redox Chemistry At Terrestrial-Aquatic Interfaces, Hermes C. Ruiz

Master's Theses

Methane (CH₄) emissions at terrestrial–aquatic interfaces (TAIs) are significant contributors to the global carbon budget, yet the mechanisms driving methanogenesis remain poorly understood. Limited data exist on how seasonal variations and redox processes influence CH₄ fluxes in these dynamic ecosystems. This study addressed two questions: (1) How are CH₄ fluxes in riverine floodplains and adjacent hillslopes impacted by seasonal variations? (2) What roles do metal redox processes (e.g., iron (Fe)) play in regulating methanogenesis?

In-situ CH₄ flux and solid-phase Fe speciation were quantified in East River, CO, under flooded and drained conditions. Groundwater chemistry, gas flux, and soil physical properties …

Mantle Flow And Fault Zone Related Seismic Anisotropy Revealed By A Dense Linear Broadband Array In Southeast Tibet, Jing Wu, Yinshuang Ai, Stephen S. Gao, Peixi Huang, Fansheng Kong, Deke Xu, Jianguo Song, Xinyu Gao, Mengyi Wei, Long Li, Jien Zhang, Yanbin Zhang, Yingying Zhang

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Southeast Tibet, a key region for the southeastward extrusion of the Tibetan Plateau, remains debated in terms of its tectonic deformation in response to the ongoing collision between the Indian and Eurasian plates. In this study, we applied shear-wave splitting analysis of core-refracted phases recorded by a newly deployed dense seismic array and six permanent stations to delineate crustal and mantle deformation processes. The observed fast polarization directions are predominantly aligned NNW–SSE, while the splitting delay times vary across four sub-blocks. The anisotropy pattern suggests a dominantly asthenospheric origin, consistent with southeastward-directed mantle flow associated with the extrusion of the …

Geol 64: Planetary Geology - Syllabus, Dara Laczniak

Open Educational Resources

This Open Educational Resources (OER) syllabus is for an introductory planetary geology course that utilizes results from space missions to expose students to the surface features, composition, geological activity, and probable history of the planets, moons, asteroids, and comets of the solar system. It also places space exploration into the context of larger societal issues such as global warming and natural resource availability and addresses topics such as the ethics of space exploration and hazards of space travel. This OER syllabus aims to foster student-centered learning, critical thinking, data analysis and communication skills, and creativity. Assigned readings are compiled into …

Morphology And Distribution Of Lakes Under The Laurentide Ice Sheet: Implications For Ice Flow Dynamics, Sarah M. Principato, Carissa Mobley

Environmental Studies Faculty Publications

This study examines the distribution and morphology of lakes under the Laurentide Ice Sheet (LIS) to investigate relationships with ice flow velocity, bedrock and basal thermal regime. Palaeo-ice streams and lobes were important components of the LIS, and properties of lakes in those regions are quantified at high resolution. Lake polygon shapefiles obtained from the HydroLAKES database contain data including water depth, volume and elevation. ArcGIS Pro is used to measure lake area, length, width, elongation, orientation, parallel conformity, density and packing. Approximately 982 282 natural lakes were identified in the region of North America covered by the maximum extent …

Impact Of Mining Activities On Land Use Land Cover (Lulc) Using Geospatial Techniques In The Obuasi Municipality, Jonathan Arthur Quaye-Ballard, Samira Naa Yemoley Nsiah, Jephthah Marfo Nimoh, Titus Tienaah, Tina Dzigbordi Wemegah, Precious Adwoa Okyere

Publications

Introduction: Sustainable development, which balances economic, social, and environmental factors to meet the needs of the present and future generations, is a collective responsibility. Rapid population growth and intensification of socio-economic activities are causing significant changes in Land Use Land Cover (LULC), directly impacting ecosystem services, biodiversity, and climate. The Obuasi community is already facing environmental degradation and health problems due to gold mining.

Methodology: The study assessed the spatial extent and intensity of mining activities in the Obuasi Municipality on the LULC and predicted future LULC changes due to mining activities using geospatial techniques. The LULC changes were analysed …

Well Spacing Optimization Technology For Coalbed Methane Horizontal Wells, Wang Yuting, Yang Yanhui, Zhang Cong, Wang Xiuwei, Liu Zhong, Chen Jiale, Dong Qing, Sun Tao, Zhang Wuchang, Li Kexin, Wang Qi

Coal Geology & Exploration

Background Well spacing design directly affects the resource utilization and exploitation benefits of blocks. Rational well spacing design plays a significant role in the commercial exploitation of coalbed methane (CBM) fields. Since the beginning of China’s 14th Five-Year Plan, blocks for CBM production in the southern Qinshui Basin have experienced a gradual increase in burial depth, a progressive decline in permeability, and a constant update of primary exploitation technology. Consequently, traditional well spacings fail to meet the requirements for field CBM exploitation any longer. Methods This study investigated the western Qinnan – eastern Mabi block by combining numerical simulations with …

Geochemical Characteristics And Genesis Of Element Enrichment Of Niobium-Rich-Rare Earth Metal Layer In Longtan Formation Of Zhina Coalfield, Ding Yunlong, Wang Fangfa, Li Bi, Tang Lifang, Yang Yi, Li Shangyuan, Wang Xiaofang, Zou Yinhong, Wang Yang

Coal Geology & Exploration

Background With the increasing demand for strategic metals and the gradual depletion of traditional metal deposit resources, coal and coal-bearing rock series are considered to be potential sources of rare metals, and coal series associated has become one of the main directions of current mineral exploration. A set of coal measure strata rich in niobium (Nb) and rare earth elements (REE) has been found in Zhina coalfield, western Guizhou and the contents of Nb and REE are as high as 334.89 μg/g and 1014.51 μg/g, respectively. This discovery is of great significance to the theoretical study of coal measure metal …

Advances In Research On The Activation And Recovery Of Strategic And Critical Valuable Metals From Coal Fly Ash, Wang Yuhao, Dong Zhongbing

Coal Geology & Exploration

Background Coal fly ash, a bulk solid waste byproduct from coal-fired power generation, has a global annual output exceeding 0.75 billion tons. Its disordered piling poses severe environmental risks, such as the generation of heavy metal leachate and PM_2.5 emissions. However, coal fly ash is rich in aluminum (Al 100‒200 mg/g), gallium (Ga 10‒300 μg/g), lithium (Li 1 300‒3 700 μg/g), and rare earth elements (REEs 200‒800 μg/g), establishing it as a potential alternative resource of strategic metals. Methods By analyzing the current domestic and international technologies for metal recovery from coal fly ash, this study expatiates on the …

Hybrid Differentiator-Based Method For Estimating The Drilling Speed Of A Vehicle-Mounted Drilling Rig During Surface Drilling For Mine Rescue, Wang Yunfei, Zhao Jiyun, Hu Yongjie, Zhang Zongyang, Pan Xiaochen

Coal Geology & Exploration

Background Vehicle-mounted drilling rigs (VMDRs), key devices in surface drilling for mine rescue, directly connect the ground and underground disaster-hit areas through vertical drilling, thereby creating rescue channels for trapped people. In this case, the drilling speed of VMDRs serves as an important indicator for evaluating surface drilling operations. However, directly determining the drilling speed is challenging due to the limitations of position sensors. Methods This study developed an estimation method based on a new hybrid differentiator (NHD), allowing the drilling speed to be calculated using measurable displacement signals. First, a continuous switching function was devised, and its convergence characteristics …

Methodology And Integration For Dynamic Safety Assessment And Early Warning Of Drilling Sites For Emergency Rescue After Underground Space Collapse, Xie Zhongzhi, Zhang Guohua, Wei Xingtong, Zhang Ning, Wang Xiaotian, Ni Xiaoyang, Zhou Zhengwen, Wang Xianze

Coal Geology & Exploration

Objective IGiven the lack of methods for dynamic safety assessment related to disasters in drilling site environments for emergency rescue after underground space collapse, this study proposed a multisource data-driven methodology for dynamic safety assessment and real-time early warning. Methods By comprehensively considering the disaster-inducing environment and disaster-causing factors at drilling sites for emergency rescue, this study established the safety assessment indices of the environment and their grading system. By integrating multi-source data on surrounding rock deformation, gas concentration, and drilling rig vibration, this study developed a safety assessment method through combination weighting achieved using the analytic hierarchy process (AHP) …

Digital Rock Modeling And Elastic Simulations Of Fractured-Vuggy Carbonate Reservoirs, Zhu Wei, Zhao Luanxiao, Wang Yirong

Coal Geology & Exploration

Objective The Tarim Basin exhibits extensively distributed deep fractured-vuggy carbonate reservoirs. Therefore, determining the seismic and petrophysical characteristics of carbonate reservoirs with a fracture and vug system will provide significant guidance for the exploration, discovery, drilling, and exploitation of favorable reservoirs in the basin. Variations in the filling state of dissolution fractures and vugs will lead to significantly different elastic and attenuation characteristics of the reservoirs. Methods Based on geological insights into the geometric structural and filling characteristics of the dissolution fracture-vug system in the outcrop sections of carbonate strata in the Tarim Basin, this study proposed a digital rock …

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

Fracturing Evolution Mechanisms Of Eroded Coals Under The Temperature Effect Of The Co2-H2O System, Lin Baiquan, Shi Yu, Liu Ting, Shen Yang, Huang Tao

Coal Geology & Exploration

Background Injecting hot flue gas produced and discharged by gas-fired power plants into deep coal seams where gas is difficult to extract enjoys dual benefits: gas production growth and geologic CO₂ sequestration. However, there is an urgent need to determine the impact of the heat-carrying property of hot flue gas on the stability of coal reservoirs. To address this issue, the key is to clarify the fracturing evolution mechanisms of eroded coals under the temperature effect of the CO₂-H₂O system.Methods Using the independently built platform of CO₂-H₂O-coal interactions that consider …

Advances In Research On Geological Evaluation Of Compressed Air Energy Storage In Underground Gas Storage Facilities, Jiang Wen, Huang Leqing, Zhang Songhang, Ma Huiying

Coal Geology & Exploration

Background Against the backdrop of achieving peak carbon dioxide emissions and carbon neutrality globally, renewable energy has developed rapidly and is gradually changing the world's energy mix. However, the intermittent and fluctuating nature of photovoltaic and wind power energy is prone to cause grid frequency fluctuations and reduced power supply reliability. Compressed air energy storage (CAES) technology has emerged as the key to the stable operation of the green power grid thanks to its large capacity and low cost.Methods Based on a systematic review of domestic and international literature in recent years, this study organizes the current theoretical and …

Macroscopic Failure Characteristics And Seepage Pattern Of Damaged Goaf-Side Coal Pillars Under Confined Water Accumulation, Liu Weitao, Chen Dongqi, Liu Yuben, Du Yanhui, Zhao Jiyuan

Coal Geology & Exploration

Background The method of supporting roadways using small coal pillars has been widely applied in China. As a result, the stability of goaf-side coal pillars affects mining safety. Resulting from multiple disturbance effects, coal pillars tend to contain various types of damage fractures. The confined water environment in goaves with water accumulation might cause the instability failure of damaged goaf-side coal pillars. Methods To investigate the impacts of the damage fracture structure on coal stability, this study introduced the concept of relatively stable initial damage fractures. Based on the theory of damage mechanics, this study constructed hydro-mechanical-damage (HMD) coupling models …

Pseudo-2d Mt Inversion Technique For Small-Frame Tem And Its Application In Advance Geological Prediction, Han Ziqiang, Wanma Longzhi, Li Xiangfeng, Yang Yongqiang, Zhu Xiaoming, Luo Chengxian, Tang Li

Coal Geology & Exploration

Objective To address the bottlenecks of low computational efficiency and impracticality of multi-dimensional inversion in the advance geological prediction based on the transient electromagnetic method (TEM), this study developed a pseudo-two-dimensional (2D) magnetotelluric (MT) inversion technique for small-frame TEM based on time-frequency transformation. Methods First, this study corroborated the significant similarity between the late-time apparent resistivity derived using small-frame TEM and the Cagniard apparent resistivity in the MT method under the parameters commonly used in advance geological prediction. Then, the optimal time-frequency transformation coefficient (C_TF) was introduced to achieve a rapid conversion from the late-time apparent resistivity …

Mechanisms Behind The Cross And Fusion Of Gas Migration And Storage Zones Under The Influence Of The Mining Height Of Fully Mechanized Mining Faces, Zhao Pengxiang, Guo Xu, Wang Chao, Li Shugang, Zhuo Risheng, Chang Zechen, Lei Wen

Coal Geology & Exploration

Objective The mining height of coal seams along fully mechanized mining faces significantly influences the formation and evolution of fractures in the overburden, as well as the characteristics of gas migration and storage zones. Investigating the influential patterns under varying mining heights will provide guidance for the arrangement of gas extraction boreholes, thus enhancing gas extraction efficiency. Methods This study investigated mining face 203 in the Tianchi Coal Mine in Heshun County, Shanxi Province. By integrating methods such as physical simulation experiments with similar materials, theoretical analysis, and engineering verification, this study systematically examined the developmental characteristics of fractures in …

Impacts Of Co2/Ch4/N2 Adsorption/Desorption On The Macromolecular Structure Of Anthracite: Insights From In Situ Raman Spectroscopy, Wang Tian, Pan Jienan, Li Meng, Wang Kai, Tang Zhuyun, Cheng Nannan, Hou Quanlin

Coal Geology & Exploration

Objective and Methods The adsorption/desorption of coalbed methane (CBM) not only induces the macroscopic deformations of coals but also significantly alters their macromolecular structures, with different gases exhibiting greatly varying mechanisms and influence degrees. Utilizing an independently developed in situ laser Raman spectroscopy system, this study revealed the differential structural responses and mechanisms of anthracite under CO₂, CH₄, and N₂ injection. Results and Conclusion Experimental results indicate that gas injection led to notable blue shifts in the D₄, D, D₃, and G peaks characterizing the microcrystalline structures of coals. In contrast, …

Log-Based Identification Of Sedimentary Facies In Coal Measures In The Southern Wuxiang Block, Shanxi Province, China, Jin Yi, Tian Yunqing, Song Huibo, Hu Bin, Yu Zhenfeng

Coal Geology & Exploration

Objective The Carboniferous and Permian coal-bearing strata in the southern Wuxiang block, Qinshui Basin, Shanxi Province, China contain abundant coalbed methane (CBM) resources. To develop intelligent discrimination technology for CBM exploration in this block, it is necessary to establish lithology discrimination criteria based on log data, reveal the response relationships between logging and sedimentary facies, and determine sedimentary patterns. Methods Using a comprehensive analysis of lithologies, sedimentary facies, and logging facies, this study systematically investigated the distributions of logging and sedimentary facies in the Shanxi and Taiyuan formations—the primary coal-bearing strata in the southern Wuxiang block. By comprehensively analyzing the …

Fractures And Their Macro-Mesoscopic Mechanical Evolution Pattern In Coals In The Benxi Formation, Ordos Basin, Zhu Boxu, Yang Xu, Li Gaoren, Li Gao, Feng Jiaxin

Coal Geology & Exploration

Objective This study aims to determine the relationship between multi-scale fracture characteristics and the mechanical behavior of deep coals, thereby helping gain further insights into the mechanisms behind the macro-mesoscopic damage and failure of the coals and providing a scientific basis for the stability assessment and mechanical modeling of deep coalbed methane (CBM) reservoirs. To this end, it is necessary to examine the differences in the coals’ mechanical properties under varying scales. Methods This study conducted uniaxial and triaxial mechanical tests, nanoindentation experiments, and CT scanning of the No. 8 coal seam in the Benxi Formation within the Ordos Basin. …

Spatial Distribution Of Coalbed Methane Migration Pathways And Selection Of Optimal Target Areas For Coalbed Methane Extraction For Abandoned Mines, Liu Qinjie, Yang Youxing, Wu Benniu, Duan Minke, Deng Zhuoyue, Guo Chenye, Sun Qiang

Coal Geology & Exploration

Objective and Methods The spatial distribution and long-term evolution of effective migration pathways determine the migration pathways of residual coalbed methane (CBM) in abandoned mines. Furthermore, they provide an important basis for selecting the optimal target areas for CBM extraction drilling in abandoned mines and maximizing extraction efficiency. This study investigated the first mining area at the first horizontal elevation of the Songzao Coal Mine in Chongqing. Using a comprehensive approach that integrated theoretical analysis, numerical simulations, and physical simulation experiments using similar materials, this study systematically examined the distribution patterns of effective CBM migration pathways in abandoned mines under …

Mechanisms Underlying Responses Of Pore Structures In Continental Oil Shale To Microwave Pyrolysis, Lyu Pengrui, Yuan Shihao, Geng Jishi, Li Delu, Zhang Huiyuan, Ge Zhenlong

Coal Geology & Exploration

Objective and Methods Microwave pyrolysis technology holds great potential to achieve clean energy conversion and efficient energy utilization of oil shale resources. This study investigated oil shale in the Triassic Yanchang Formation, Ordos Basin. Through microwave pyrolysis experiments under different power values (600 W, 800 W, and 1000 W) conducted using a microwave equipment monitoring system, this study tested the gas products generated during pyrolysis. Using the nitrogen adsorption method, this study compared and analyzed the pore structure characteristics between the original oil shale and samples after microwave heating under different power values. Additionally, the mechanisms behind damage to oil …

Spatiotemporal Evolution Pattern Of The Inertial Horizontal Displacement Of Mining Overburden And A Surface Prediction Model Considering Inertial Horizontal Displacement, Chen Yuanfei, Wang Lei

Coal Geology & Exploration

Objective Substantial measured data indicate that the along-strike horizontal displacement of the surface tends to be nonzero in the central part of the mining-affected zone. This phenomenon deviates from traditional understanding, leading to systematic deviations in the predicted results of the traditional prediction model for horizontal displacement. Methods This study investigated mining face 1414 of the Guqiao Coal Mine in the Huainan mining area, Anhui Province. Using measured data and numerical simulation methods, this study explored the spatiotemporal evolution of the horizontal displacement within the mining overburden and of the surface. Then, it analyzed the sources, patterns, and distribution characteristics …

Deterioration And Instability Mechanisms Of Water-Rich And Weakly Cemented Open-Pit Slopes, Wang Ming, Wu Zhang, Xu Changyou, Zhao Fu, Meng Xiangchun, Shi Bin, Liu Jingyu, Xu Yongchao, Wang Jingwei, Zhao Lichun

Coal Geology & Exploration

Background During the mining of an open-pit mine, denudated layers contain loose Neogene and Quaternary aeolian, alluvial, and diluvial deposits, facilitating water storage and conduction. This is prone to cause slope degradation and instability, severely threatening mining safety. Methods Based on results from field surveys and laboratory experiments, this study systematically analyzed the impacts of groundwater on the weak layer along a slope of an open-pit mine in the Huolinhe Coalfield, Inner Mongolia, focusing on its softening effect on mudstones. By establishing a mechanical model for unconsolidated strata, this study derived an equation for calculating the seepage force in the …